1. Field of the Invention
This invention relates to display methods and apparatus.
More particularly the invention relates to such methods and apparatus for using data representing a three-dimensional surface to produce a two-dimensional display representing a perspective view of the surface.
In the present specification the term perspective view includes a quasi-perspective view, e.g. an isometric view.
One particular application of such methods and apparatus is in an aircraft for providing a pilot with a real time display of the ground terrain ahead of the aircraft e.g. to assist navigation in poor visibility. Another application is in aircraft flight simulators.
2. Description of Related Art
In known such methods and apparatus the display comprises a perspective view of an array of elements appearing to model the surface, the array appearing to be fixed with respect to the surface. Such a display is satisfactory in many environments, but when used in a high speed, high stress environment, such as a combat aircraft, can present a display which changes confusingly with observer motion.